1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Travka [436]
3 years ago
13

Calculate the amount of heat (kcal) released when 50.0g of steam at 100*c hits the skin, condenses, and cools to a body temperat

ure of 37*c
Physics
2 answers:
abruzzese [7]3 years ago
7 0

conversion of steam at 100 C to water at 100 C :

m = mass of the steam = 50 g

L = latent heat of condensation of steam to water = 79.7 J/g

Heat released in conversion of steam to water is given as

Q₁ = mL

inserting the values

Q₁ = (50) (79.7)

Q₁ = 3985 cal


conversion of water at 100 C to water at 37 C :

ΔT = change in temperature = 100 - 37 = 63 C

c = specific heat of water = 1 cal/(gC)

m = mass of water = 50 g

Heat released in change of temperature is given as

Q₂ = m c ΔT

Q₂ = 50 x 1 x 63

Q₂ = 3150 cal

total heat released is given as

Q = Q₁ + Q₂

Q = 3985 + 3150

Q = 7135 cal

luda_lava [24]3 years ago
6 0
As the steam touches the skin, it undergoes a phase change and releases latent heat due to the phase change. As it reaches equilibrium, it releases sensible heat. We calculate as follows:

Q = latent heat + sensible Heat
Q = 2.26 kJ / g (50.0 g) + 50.0 g ( 4.18 J / g C) (37 C - 100 C) ( 1 kJ / 1000 J)
Q = 99.833 kJ
You might be interested in
When children use the word “doggie” to refer to every four-legged animal they see, __________ occurs.
Oduvanchick [21]
This is known as overextension! (the correct answer is B.)
7 0
3 years ago
An inventor claims to have invented a heat engine that receives 750kJ of heat from a source at 400K and produces 250kJ of net wo
IRISSAK [1]

Answer:

the claim is not valid or reasonable.

Explanation:

In order to test the claim we will find the maximum and actual efficiencies. maximum efficiency of a heat engine can be found as:

η(max) = 1 - T₁/T₂

where,

η(max) = maximum efficiency = ?

T₁ = Sink Temperature = 300 K

T₂ = Source Temperature = 400 K

Therefore,

η(max) = 1 - 300 K/400 K

η(max) = 0.25 = 25%

Now, we calculate the actual frequency of the engine:

η = W/Q

where,

W = Net Work = 250 KJ

Q = Heat Received = 750 KJ

Therefore,

η = 250 KJ/750 KJ

η = 0.333 = 33.3 %

η > η(max)

The actual efficiency of a heat engine can never be greater than its Carnot efficiency or the maximum efficiency.

<u>Therefore, the claim is not valid or reasonable.</u>

3 0
3 years ago
Why metals have thermoconductivity higher than ceramic?
Pie

Answer:

Thermal Conductivity Easily Transmits Heat Among Fine Ceramics

4 0
2 years ago
An object of mass m moving at a speed of v1 possesses kinetic energy that is equal to KE1. When the object's speed is doubled, t
Vera_Pavlovna [14]

Answer:

KE₂ = 4KE₁

Explanation:

KE₁ = ½mv₁²

KE₂ = ½mv₂²

KE₂ = ½m(2v₁)²

KE₂ = 4(½mv₁²)

KE₂ = 4KE₁

7 0
2 years ago
The rate of turn at any airspeed is dependent upon
bagirrra123 [75]

Answer:

the rate of turn at any airspeed is dependent upon the horizontal lift component

6 0
2 years ago
Other questions:
  • A ball of mass m and radius R is both sliding and spinning on a horizontal surface so that its rotational kinetic energy equals
    11·1 answer
  • Complete combustion of 1.0 metric ton of coal (assuming pure carbon) to gaseous carbon dioxide releases 3.3 x 1010 j of heat. co
    10·1 answer
  • How are waves used on an everyday basis?
    5·2 answers
  • Black holes have three major parts that include:
    6·2 answers
  • A horizontal disk rotates about a vertical axis through its center. Point P is midway between the center and the rim of the disk
    5·1 answer
  • Gave the examples of Civil law​
    10·2 answers
  • What is the definition for scientific model?​
    9·2 answers
  • Can anyone help me in this question?
    5·1 answer
  • 1. A truck with a mass of 8, 000 kg is traveling at 26.8 m/s when it hits the brakes. A.)What is the momentum of the truck befor
    6·1 answer
  • Solve the science problem
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!